Refrigeration system embodying provisions for distributing liquid



Aug. 24, 1954 w. G. KOGEL 2,687,622

REFRIGERATION SYSTEM EMBODYING PROVISIONS FOR DISTRIBUTING LIQUID FiledApril 26, 1950 3 Sheets-Sheet l INVE TOR. [W I wflm l arm/Mfr g- 1954 w.G. KOGEL 2,687,022; REFRIGERATION SYSTEM EMBODYING PROVISIONS FORDISTRIBUTING LIQUID' Filed April 26, 1950 s Sheets-Sheet 2 Aug. 24, 1954w KOGEL 2,687,022

REFRIGERATION SYSTEM EMBODYING PROVISIONS FOR DISTRIBUTING LIQUID FiledApril 26, 1.950 3 Sheets-Sheet. 3

W IN VfN OR.

iaw/ QM armmm'y Patented Aug. 24, 1954 REFRIGERATION SYSTEM EMBODYINGPROVISIONS FOR DIS TRIBUTIN G LIQUID Wilhelm Georg Kogel, Stockholm,Sweden, as-

signor to Aktiebolaget Elektrolux, Stockholm, Sweden, a corporation ofSweden Application April 26, 1950, Serial No. 158,126 Claims priority,application Sweden June 28, 1949 i tion type.

It is an object of the invention to provid an improvement in systems ofthis type for splitting and dividing absorption liquid into a pluralityof paths of flow.

Another object is to provide such an improvement for dividing absorptionliquid into several paths of flow for controlling the manner in whichweak absorption liquid flows through an absorber.

A further object is to provide such an improvement for recirculating apart of the raised ab sorption solution through a vapor lift tube orpump and only circulating a part of the raised liquid through theabsorber of the refrigeration system.

. A still further object is to provide an improvement in a vapor-liquidlift pump in which the pumping ratio is sufficiently high to insurereliable pumping and at the same time provision is made for circulatingabsorption liquid through the absorber at an effective pumping ratiowhich is relatively low to insure satisfactory performance and efficientoperation of the absorber.

A still further object is to provide such an improvement for dividingabsorption liquid to divert a part of the liquid, which contains aprotective corrosion inhibiting substance, into places not ordinarilywashed by absorption liquid.

. The invention, together with the above and further objects andadvantages thereof, will be more fully understood upon reference to thefollowing description and accompanying drawings forming a part of thisspecification, and of which:

Fig. 1 illustrates more or less diagrammatically a refrigeration systemembodying the invention;

Fig. 2 is a view like that of Fig. 1 illustrating another embodiment ofthe invention;

Fig. 3 is a fragmentary view of a part of the system like that shown inFig. 2 illustrating a modification of th invention; and

Fig. 4 is a fragmentary View of a system similar to that shown in Figs.1 and 2 illustrating a further embodiment of the invention.

Referring to Fig. 1, I have shown my invention in connection with anabsorption refrigeration system of a uniform pressure type which is wellknown in th art and in which a pressure equalizing gas is employed. Sucha refrigeration system comprises a vapor expulsion unit ill including agenerator or boiler ll containing a refrigerant, such as ammonia, insolution in a body .of absorption liquid, such aswater. Heat is suppliedto the boiler II from a heating tube or flue l2 thermally connectedtherewith at i l, as by welding, for example. The heating tube i2 may beheated in any suitable manner, as by an electrical heating elementdisposed within the lower part of the tube or by a liquid or gaseousfuel burner it which is adapted to project its flame into the lower endof the tube.

The heat supplied to the boiler l I and its contents expels refrigerantvapor out of solution, and, as will b described more fully hereinafter,the vapor passes upwardly from the vapor expulsion unit Iii through anair cooled rectifier 16 into an air cooled condenser film which it iscondensed and liquefied. Liquid refrigerant flows from condenser i7through a U-shaped conduit 18 into a cooling element or evaporator E9 inwhich it evaporates and difiuses into an inert pressure equalizing gas,such as hydrogen, which enters the lower end thereof from a gas heatexchanger 20. Due to evaporation of refrigerant fluid into inert gas, arefrigerating effect is produced with consequent absorption of heat fromthe surroundings.

The rich gas mixture of refrigerant vapor and inert gas formed incooling element l 9 flows from the upper part thereof through a conduit2 i, one passage 22 of gas heat exchanger 20, conduit 23 and absorbervessel 24 into the lower end of an absorber coil 25. In absorber coil 25th rich gas mixture flows countercurrent to downwardly flowingabsorption liquid which is introduced into the absorber through conduits25 and 2'! in a manner to be described presently. The absorption liquidabsorbs refrigerant vapor from inert gas, and inert gas weak inrefrigerant flows from absorber coil 25 through another passage 28 ofthe gas heat exchanger 20 into the lower part of cooling element iii.

The circulation of gas in the inert gas circuit just described is due tothe difference in specific weight of the columns of gas rich and weak,respectively, in refrigerant vapor. Since the column of gas rich inrefrigerant vapor and flowing from cooling element [9 to the absorbercoil 25 is heavier than the gas weak in refrigerant and flowing from theabsorber coil 25 to cooling element i9, a force is produced or developedwithin the system for causing circulation of inert gas in the mannerdescribed.

Absorption solution enriched in refrigerant flows from the absorbervessel 24 through a conduit 29 and a passage or pipe 30 of liquid heatexchanger 3| disposed about the lower part of the vapor expulsion unit.Such enriched absorption solution is conducted from the passage or pipe3% through a connection 32 into a vertically extending pipe 33 at apoint 34 which is at a level below the liquidsurface level in the absorber vessel 2t and also below the surface level of the column ofliquid contained in the pipe 33. The extreme lower end of pipe 33 isclosed and in communication with the lower end of a vapor lift pipe 35in thermal exchange relation with th heating tube I2 at 36, as bywelding, for example. Liquid is raised by vapor-liquid lift actionthrough pipe 35 into the upper part of boiler l l. Refrigerant vaporexpelled out of solution in boiler I, together with refrigerant vapordischarged from the upper end of pip 35, flows upwardly from the vaporexpulsion unit H] to the condenser I! in a manner to-be describedpresently. The outlet end of condenser I! is connected by a conduit 31to a part of the gas circuit, as to the upper part of absorber coil 25,for example, so that any inert gas which may pass through the condenserl'l'can flow to the gas circult.

In refrigeration systems of the kind being de scribed it is oftendesirable tosplit up and divide liquid circulating in the system into anumber of separate streams. In manyinstances there is a requirement oftaking liquid in its path of flow and accurately dividing such fiowingliquid into several streams whereby a definite part or percentage of theliquid will flow in each stream. In accord-with my invention I providean improvement for reliably dividing absorption liquid circulating inthe system which in Fig. l is advantageouslyembodiedin the vaporexpulsion unit lb. The liquid divider of Fig. 1 is associated wtih thevapor lift pipe 35 whose upper end extends into a vessel 38. The upperpart of pipe 35 in its lengthwise direction is provided with aseparating or dividing wall 39, such wall 39 not only serving as aseparating or dividing member for the pipe 35 but also for the vessel38.

The upper end of pipe 35 at opposite sides of the separating wall39- isformed with openings 4!] and 4| through which absorption liquid passeswhile being raised through the pipe 35- by vaporliquid lift action. Theupper ends of conduits 42 and 43 are connected to the vessel 35 atapproximately the same level which is slightly below the openings and Min vapor'lift pipe 35. Raised liquid passing through opening at flowsfrom the right-hand side of vessel 38 through conduit 43 into the upperpart of boiler ll. Raised liquid passing through opening 3!} flows fromthe left-hand side of vessel 3?; through conduit 52 whose lower end isconnected to the outer passage or pipe 44 of the liquid heat exchanger3!.

The vessel 38 serves not only as theplace where division of liquidoccurs but also as a vapor separator in which lifting vapor is separatedfrom raised liquid. Vapor expelled out of solution in boiler ll passesthrough conduit 43 into vessel 38 and mixes with such separated vaporwhich can pass from the upper open end ofpipe All of the vapor generatedin thevapor expulsion unit flows from the upper part of vessel 38through a conduit 45 to a region 46 in pipe 33 which is below thesurface level of the liquid column contained therein. The region as maybe referred to as an analyzer in which entering vapor bubbles throughenriched absorption solution and is analyzed, whereby absorption liquidvapor will be removed from refrigerant vapor.

After being analyzed the vapor flows upwardly through the upper part ofpipe 33 which constitues a vapor supply line leading to the aircooledrectifier l6 and air-cooled condenser H.

The principal part of generated vapor produced in the vapor expulsionunit it is expelled from solution in boiler l I due to heating by theheating tube [2, and liquid of decreasing concentration flows downwardlyin boiler ll and passes therefrom through an inner passage 41 of liquidheat exchanger 3! and conduit 27 into the extreme upper end of absorbercoil 25. As previously explained, liquid passing downwardly in conduit42 flows into the outer passage M; of the liquid heat exchanger fromwhich the liquid flows through conduit 2! into an intermediate part ofabsorber coil 25.

Since solution that is raised by vapor lift pipe 35 and passes intoboiler H is subjected to further heating in the boiler while raisedsolution passing into conduit 42 is notsubjected to such additionalheating, the absorption solution supplied to the upper part of absorber25 through conduit 26 will be substantially weaker in refrigerant thanthe solution supplied only to the lower part of the absorber 25 throughconduit 2'5. The evaporating temperature of refrigerant fluid inevaporator I9 is a function of the partial pressure of refrigerantvapor. The more effectively refrigerant vapor is absorbed from inert gasin absorber 25, the less refrigerant-vapor will be contained in theinert gas entering evaporator [9.

When inert gas enriched in refrigerant enters the lower end of absorbercoil 25, it first comes in contact with absorption solution which is amixture of solution introduced into the-absorber through both conduitsre and ill and has the highest concentration of refrigerant. Thereafter,the inert gas comes in contact with absorption solution in the upperpartof absorber 255 which has a weaker concentration of refrigerant.Thus, by subdividing absorption solution, while being moved upwardly invapor lift pipe 35, into two separate streams and conducting suchstreams of different refrigerant concentration into theabsorber 25 inthe manner'explained, the absorption solution is employed moreefficientlyand effectively to absorb refrigerant vapor from inert gas.Stated another way, the inert gas weak in refrigerant and passingthrough the extreme upper part of the absorber coil 25 will be inequilibrium with absorption solution having a concentration ofrefrigerant considerably less than that of solution in a system having aconventional absorption solution circuit.

In effect, the division of the liquid in vapor lift pipe 35 into twostreams enables the stream flowing through conduit 42 to by-pass theboiler l l which constitutes a high temperature place of vaporexpulsion. Thus, the liquid heat exchanger 3! is formed with anintermediate passage 3%) for rich absorption solution flowing from theabsorber vessel 24 to the vapor expulsion unit it, an inner passage 4!for weak absorption solution flowing from boiler l I and having thesmallest concentration of refrigerant, and an outer passage 44 for weakabsorption solution which by-passes boiler ii and has a concentration ofrefrigerant greater than that of solution flowing in the inner passage41.

The liquid divider of the invention works extremely well and has beenfound satisfactory for many liquid dividing purposes in absorptionrefrigeration systems of the kind illustrated in Fig.

1 and just described. Another useful application of the liquid dividerof the invention is illustrated in Fig. 2 in which parts similar tothose shown in Fig. 1 are referred to by the same referencenumerals towhich 100 has been added.

In Fig. 2 vapor expelled from solution in boiler I I I flows throughconduit I 43 into the upper part of vapor lift pipe I 35 and, togetherwith vapor from the upper end of the latter, flows through a conduit I48to a region I 46 in pipe I33 which serves as an analyzer and is disposedbelow the surface level of the liquid column contained therein. Thevapor generated in the vapor expulsion unit III] degresses the surfacelevel of liquid in conduit I48 so that the vapor bubbles through liquidin the pipe I33. After passing through the analyzer I 46 the vapor flowsthrough the upper extension of pipe I 33 and air-cooled rectifier IIIito condenser II! in which it is condensed and liquefied.

Liquid refrigerant flows from condenser II'I' through a conduit I49 toan evaporator or cooling element I I9 in which it evaporates or diffusesinto inert gas which enters the lower end thereof through a conduit I50.The rich gas mixture flows from the upper part of cooling element I Ithrough a conduit I5I, one passage of gas heat exchanger I20, conduitI23 and absorber vessel I24 into the lower end of absorber coil I 25. Inabsorber coil I25 the rich gas mixture flows countercurrent todownwardly flowing absorption liquid which enters through a conduit I52.Inert gas weak in refrigerant flows from the absorber coil I25 in a pathof flow including conduit I55, another passage of gas heat exchanger I25and conduit I50 into the lower end of cooling element II9.

Absorption solution enriched in refrigerant flows from the absorbervessel I24 through conduit I29 and inner pipe or passage I54 of liquidheat exchanger I3I, the upper end of which isconnected to pipe I33 at apoint I34 which is at a level below the liquid surface level in theabsorber vessel I20 and below the surface level of the liquid columnmaintained in pipe I 33. Liquid is raised by vapor-liquid lift actionfrom the lower end of pipe I33 through vapor lift pipe I35 into theupper end of boiler III. Absorption solution weak in refrigerant passesfrom boiler III through a connection I55, outer passage I56 of liquidheat exchanger I3I and conduit I52 into the upper part of absorber coilI25.

The outlet end of condenser III is connected by an upper extension ofconduit I49, vessel I51 and conduit I55 to a part of the gas circuit, asat one end of gas heat exchanger I29, for example, so that any inert gaswhich may pass through the condenser II'I can flow into the gas circuit.Refrigerant vapor not liquefied in the condenser flows through the upperpart of conduit I45 to displace inert gas in vessel I51 and force suchgas into the gas circuit. The effect of forcing gas into the gas circuitin this manner is to raise the total pressure in the entire systemwhereby an adequate condensing pressure is obtained to insurecondensation of refrigerant vapor in condenser III.

In Fig. 2 the liquid divider is provided at the upper end of vapor liftpipe I35, the latter being formed with diametrically opposed openingsI40 and MI with which the conduits I48 and I43, respectively, are incommunication. Raised liquid passing through opening I4I flows throughconduit I43 into the upper part of boiler III in which the principalpart of the vapor is generated. As previously explained, weak absorptionsolution deprived of refrigerant flows from boiler III through the heatexchanger I SI and conduit I52 to the upper part of the absorber coilI25. Raised liquid passing through opening I 40 flows through conduit I48 into the liquid column maintained in conduit I33.

Hence, liquid being raised in vapor lift pipe I35 is split-up anddivided into two streams, one of which passes to boiler II I andeventually returns to the absorber coil I25 for flow therethrough, whilethe other stream Icy-passes the boiler I I I and simply returns to theliquid column in conduit I33 from the lower end of which absorptionsolution is raised to the liquid divider through the vapor lift pipeI35. The manner in which absorption solution is split up into twostreams in the embodiment of Fig. 2 makes it possible to establish idealpumping conditions in the vapor expulsion unit IIG without circulatingan excessive quantity of solution through the absorber I25.

In a vapor-liquid lift pipe I35 of the character under consideration thepart of the lift pipe in thermal exchange relation with the heating tubeII2 may be referred to as the vapor forming part in which vapor bubblesare formed due to heat derived from the heating tube. Due to formationof these vapor bubbles which tend to collect and become larger andlarger, liquid in the lift pipe I35 becomes segregated, whereby slugs ofliquid are caused to rise in the lift pipe by vapor lift action. Suchvapor lift action of liquid is effected by reason of the fact that theinner diameter of the lift pipe I35 is sufliciently small so that vaporcannot freely pass liquid in the lift pipe. Upward movement is impartedto liquid in the vapor lift pipe I35 under the influence of a reactionhead formed by the liquid column maintained in pipe I 33. Stated anotherway, the weight of the column of liquid in pipe I33 overbalances theweight of the column of segregated liquid bodies and vapor in vapor liftpipe I35 to cause rise of liquid in the latter.

In a vapor lift pump of the kind being described the ratio of thequantity of weak absorption solution being circulated to the quantity ofrefrigerant vapor generated is referred to as the pumping ratio (1/).When reliable functioning of the vapor lift pump is a primaryconsideration, it is desirable to provide a pumping ratio in theneighborhood of 6 to 8 when ammonia is employed as the refrigerant andwater as the absorption liquid. When low evaporator temperature andperformance are viewed as the primary consideration, a pumping ratio ofabout 3.5 is more suitable. Under such conditions excessive circulationof absorption solution through the liquid heat exchanger and absorber isavoided, the liquid heat exchanger operates more efficiently and is notoverloaded, and the absorber functions better to provide for theevaporator inert gas having the weakest possible concentration ofrefrigerant.

By splitting-up the liquid in the manner shown in Fig. 2 and describedabove, it is possible to keep recirculating a part of the absorptionsolution all of the time through the vapor lift pipe. In this manner ahigh pumping ratio of the order given above can be maintained to insurereliable pumping under all operating conditions encountered without anylikelihood of damaging the lift pipe or pump due to overheating whichmay occur at a lower pumping ratio. The part of the absorption solutionthat circulates in the local acs'nozz circuit passesfrom: theupperiendof lift pipe. I35 through opening Hill'into conduit M8. The liquidflowing downwardly in conduit his passes into pipe. i313 and mixes withrich absorption solution flowing from the absorber 25. From the lowerend of pipe l33 liquid is raised through pipe I35 by vapor lift action,thus completing the local circuit for. a part of the absorptionsolution.

It will therefore be evident that only the part of'the raised'absorptionsolution passing through opening I ll' into conduit M3 and boiler ll!eventually finds its way to the absorber [25. Hence, by providing aliquid divider at the upper end of the vapor lift pipe 135, the raisedliquid can be divided into two streams of such size that one will give ahigh pumping ratio of 6 to 8 for the pump or lift pipe while the otherstream flowing to the absorber 25 effects circulation of weak absorptionsolution at a pumping ratio equivalent to about 3.5 providin such weakabsorption solution constituted the entire quantity of liquid raised bya vapor lift pipe.

In both the embodiments of Figs. 1 and 2 the liquid divider of theinvention operates in a satisfactory manner and enables liquid to bedivided and split-up in a predetermined and precise ratio. In both Figs.1 and 2 the actual division of liquid occurs at the openings formed inthe walls of the vapor lift pipes and I35, respectively. The openingslii and ll in lift pipe 35 and openings l lo and Ml in lift pipe E35 mayalso be referred to as overflow points at which regions division ofliquid takes place, the division and splitting-up of the liquid beingeffected while upward movement is being imparted to the liquid to raisethe latter from one level to a higher level at the locations of theoverflow points or regions. As previously explained, rise of liquid iseffected in the vapor lift pipes 35 and E35 by an upward motivatingforce which is under the infiuence of the reaction heads formed by theliquid columns in pipes (stand !33, respectively.

Fig. 3 is a fragmentary view of the upper part of the vapor expulsionunit ill) in which similar parts are designated by the same referencenumerals. Fig. 3 differs from Fig. 2 in that an additional conduit l59is employed which interconnects the upper parts of conduits i i-3 andH18, re-

spectively, thereby providing an unobstructed connection for vaporflowing from boiler Hi to conduit his. However, it is to be understoodthat in the embodiment of Fig. 2 vapor can flow from conduit Hill toconduit Hi8 through the upper part of vapor lift pipe 135 since vaporbubbles as well as segregated bodies of liquid rise upwardly through thelift pipe. Due to the upward motivating force to which the upwardlymoving liquid is subjected, the liquid divides into two streams in adefinite ratio which is dependent upon the surface area of the openingsHill and I4! and inversely proportional to the resistance to fluid flowoffered by the openings. While a precise and definite split-up oi theliquid intoseveral streams can be effected, itis desired to point outthat the division of liquid is not always directly proportional to thesize of the openings in thewalls of the vapor lift pipes.

In absorption refrigeration systems of the inert gas type it is oftendesirable to provide a socalled triple heat exchanger in which heatexchange is effected between (1) rich absorption solution flowing fromthe absorber to the vapor expulsion unit and (2) weak absorptionsolution flowing from the vapor expulsion. unit to theabsorberand (3')vapor which is generated inithe vapor expulsion unit and passinggtotheoondenscr of the refrigeration system. The vapor: passage of such atriple heat exchanger serves as an internal rectifier in whichabsorption liquid: Va.- por accompanying the refrigerant vaporis-removed by cooling the, mixture to condense out the absorptionliquid. When water is employed as the absorption liquid in a system inwhichthe parts and connections are formed of ferrous metal, the watercondensed by rectification usually passes into a part of the system notnormally protected by a corrosion inhibiting sub stance. In Fig. 4 isillustrated a further embodiment of the invention in which the liquiddivider. is advantageously employed to split-up intotwo streamsabsorption solution containing a. corrosion inhibitin substance, and inwhich oneof the streams is conducted to a place of rectification in thesystem. Fig. i is a fragmentary View of a system like that shown in Fig.2 in which parts like those illustrated in Fig. 2 are referred tozby thesame reference numerals to which 500 has been added.

In Fig. l vapor expelled from solution in boiler 5H flows throughconduit 5% to a region 546 in pipe 533 which serves as an analyzer.After'passe ing through analyzer 546 the vapor flows through conduitsEli) and Eli into an outer passage 512 of a triple heat exchanger 513.From the triple heat exchanger the vapor then flows through a conduit514 in which the vapors are conducted to a condenser, not shown, in thesame manner illustrated in Figs. 1 and 2 anddescribed above.

Absorption liquid enriched in an absorber flows through a conduit 529into an intermediate'pase sage 575 of the triple heat exchanger, suchenriched liquid passing from the passage 575 through a connection 53 2into pipe 533 at a point 5312; Liquid is raised by vapor lift actionfrom the lower end of pipe 533 through vapor lift pipe 535 into theupper end of boiler 5i I. Absorption solution weak in refrigerant flowsfrom boiler 51'! through an inner passage 5% of the heat exchanger andconduit 552 to the upper part of the absorber for downward flow in thelatter.

When ammonia and water are employed as the refrigerant and absorptionliquid, respectively; it is usually the practice to provide a corrosioninhibiting substance, such as sodium chromate or sodium nitrite, forexample, in the absorption liquid circuit to protect th parts of suchcircuit which are usually formed of ferrous metal; such as iron orsteel. All parts of the absorption liquid circuit in which absorption.liquid normally flows are, therefore, protected by the corrosioninhibiting substance present in the absorption liquid. In the embodimentof 4 generated vapors are introduced into the outer passage N2 of tripleheat exchanger M3, and, as previously explained, condensation ofabsorption liquid vapor is effected in such passage which serves as aninternal rectifier. When water is employed as the absorption liquid, thecondensate formed in the passage ii'ifl is water which flows by gravityinto a conduit Ell having a lower looped portion and an upwardlyextending portion in thermal relation with the heating tube l I2 at513,,as by weld;- ing, such upwardly extending portion being incommunication with the vapor space of the pipe 533.

litv now will be understood that condensate formed in passage 512 flowstherefrom by gravity into conduit and is raised in the latter by vaporlift action into the upper end of pipe 533. The passage 5Y2 ordinarilyis a place in the absorption liquid circuit which is not reached byabsorption liquid containing the corrosion inhibiting substance. Inaccord with the present invention a liquid divider is provided at theupper end of vapor lift pipe 535 whereby a part of the raised absorptionliquid can be diverted into conduit 5'. As shown, the upper end of vaporlift pipe 535 is formed with openings 54!] and 5 having conduits 5H and543 in communication therewith. As previously explained, raised liquidis split-up into two streams, one of which passes through opening 5M andconduit 543 into the upper part of boiler 5| I. The other stream passesthroughopenin 54d and flows through conduit 5'll into passage 572 of thetriple heat exchanger 573. Accordingly, the walls of the passage 512 arewashed with absorption liquid containing a corrosion inhibitingsubstance so that this part of the vapor expulsion unit 5M3 will beprotected along with other parts through which absorption liquidnormally circulates.

It will further be observed that the embodiment of Fig. 4 is similar tothat of Fig. 2 in that the part of the absorption liquid passing intoconduit 5H and bypassing the boiler 5H flows in a path of flow includingpassage 572, conduit Ell and pipe 533. From the bottom of pipe 533 theabsorption liquid is again raised by vapor lift action in vapor liftpipe 535. Hence, liquid diverted into conduit 57! passes through a localcircuit and returns to the lower end of vapor lift pipe 533 withoutpassing through the absorber. Ihe embodiment of Fig. 4- is, therefore,like that of Fig. 2 in that a higher pumping ratio can be maintained forvapor lift pipe 535 while weal:

absorption liquid can be supplied to the absorber .at a rate which isequivalent to a considerably lower pumping ratio for the vapor liftpipe.

In the embodiments illustrated in Figs. 1, 2, 3 and 4 described above,it will be seen that the vaporlift pipes 35, 35 and 535 essentiallyconstitute places of pumping at which absorption liquid is raised fromone level to a higher level. The openings Hill and Ml at the upper endof pump pipe in 2, and similar openings in the pump pipes of the otherembodiments, are provided at the places of pumping for spliting theabsorption liquid in the act of raising the liquid from a low to ahigher level.

In Fig. 2, as in all of the other embodiments illustrated and described,the openings I as and t ll at the vicinity of the upper end of pipe I35are in spaced apart relation and communicate with spaced apartperipheral regions of the single rising liquid column in the verticallyextending pipe. Upward movement of liquid is effected in an individualstream by raising successive increments thereof progressively higher insuch single rising column under the influence of a liquid head formed byliquid in the system. Liquid in the individual stream is divided byspilling liquid directly from the spaced apart peripheral regions of thesingle rising liquid column, as at the openings I49 and MI in Fig. 2,for example, the liquid approaching such openings only while ascendingand moving upwardly to the higher level. Hence, the openings MD and Miare formed in Fig. 2 in a section of the pump pipe I35 through whichliquid is only ascending and moving upwardly to the higher level.

In Fig. 2, the pipe or conduit M8 forms part of a local circuit intowhich a part of the liquid,

10 while moving upwardly in the pump pipe 935, is constantly beingdiverted through the opening Mt. Such diverted liquid flows in a path offlow which by-passes the standpipe Ill and the absorber and flows fromthe conduit Hi8 through conduit l 33 to the lower end of the pump pipeI35.

Although I have shown and described particular embodiments of myinvention, it will be obvious to those skilled in the art that variouschanges and modifications may be made, and that certain features may beemployed independently of others, without departing from the spirit andscope of the invention. I, therefore, aim in the following claims tocover all such modifications and changes as fall within the true spiritand scope of the invention.

What is claimed is:

1. In an absorption type refrigerating system containing absorptionliquid, a first vertically extending conduit having an inlet at thelower end thereof, said first conduit providing a passage in which vaporcannot freely pass liquid therein, means comprising a source of heatexternal to the system for heating said first conduit to effect upwardmovement of liquid therein by vapor lift action under the influence of areaction head in the system, the wall of said first conduit havingopenings at spaced apart regions, and sec- 0nd and third conduitscommunicating with said openings, said openings serving as overflowpoints through which liquid moving upwardly in said vertically extendingconduit passes so as to divide such liquid into a number of separatestreams for flow through said second and third conduits communicatingwith the openings.

2. Apparatus as set forth in claim 1 including a separating or dividinmember extending lengthwise of said first conduit and within the latter,the wall of said first conduit havingsaid openings at opposite sides ofsaid dividing memher.

3. Apparatus as set forth in claim 1 including a vessel in which theupper end of said first conduit extends, a separating or dividing memberextending lengthwise of said first conduit for dividing the latter andsaid vessel into two chambers whose upper parts are in open vaporcommunication with one another, the wall of said first conduit havingsaid openings Within said vessel at opposite sides of said dividingmember, and each of said second and third conduits being connected tosaid vessel to receive liquid passing through one of said openings.

4. Apparatus as set forth in claim 3 in which the upper end of saidfirst conduit is in communication with the vapor space of said vessel.

5. Apparatus as set forth in claim 1 in which the upper end of saidfirst conduit is closed and said openings are spaced from such upperclosed end.

6. Apparatus as set forth in claim 1 in which the extreme upper end ofsaid first conduit is closed, and an open vapor connection between saidsecond and third conduits.

7. In the art of refrigeration with a system having a path of flow forabsorption liquid, the improvement which comprises moving such liquid inthe system in an upward direction in an individual stream from a firstlevel to a higher level, effecting such upward movement of liquid in theindividual stream by raising successive increments thereof in a singlerising fiuid column of segregated bodies of liquid and vapor by vaporlift action under the influence of a reaction head formed by liquid inthe system, spilling liquid directl from said upwardly moving liquidbodies at the region of said higher level at spaced apart points of saidsingle fluid column, and flowing in a separate path of flow by gravityaction a part of the rising liquid spilling at each of said overflowpoints at the instant such liquid leaves the single rising fluid columnand is no longer affected by said reaction head.

8. In the art of refrigeration with a system having a place ofabsorption and a place of pumping at which absorption liquid is raisedor lifted from one level to a higher level by vapor lift action forgravity flow to the place of absorption, the improvement which comprisessplitting the absorption liquid into two streams at the place of pumpingin the act of raising liquid from said one level to said higher level,and, at all times while the absorption liquid is being lifted by vaporlift action, simultaneously flowing liquid in one of said streams tosaid place of absorption and flowing liquid in said other stream to saidplace of pumping for recirculation therethrough without passing throughsaid place of absorption.

9. The improvement set forth in claim 8 in which the absorption liquidcontains a corrosion inhibiting substance, the further step of flowingliquid in said other stream to a place in the system in which absorptionliquid normally does not circulate and thereafter to said place ofpumping for recirculation therethrough without passing through saidplace of absorption.

10. The improvement set forth in claim 8 in which the absorption liquidcontains a corrosion inhibiting substance and vapor is expelled fromsolution at a place of vapor expulsion, the further steps of flowingexpelled vapor in a path of flow through a place of rectification to aplace of condensation, and flowing liquid in said other stream throughsaid place of rectification and thereafter to said place of pumping forrecirculation therethrough without passing through said place ofabsorption.

11. The improvement set forth in claim 10 which further includes thestep of raising liquid from said place of rectification by vapor liftaction so to enable such raised liquid to flow by gravity to said placeof pumping for recirculation therethrough without passing through theplace of absorption.

12. The improvement set forth in claim 8 in which the absorption liquidcontains a corrosion inhibiting substance, the system having anabsorption liquid circuit including a place of vapor expulsion and saidplace of absorption and in which circulation of liquid is effected byvapor i lift action at said place of pumpingthe further steps whichinclude flowing vapor generated at said place of vapor expulsion in afirst path of flow to a place of condensation, flowing liquid in saidone stream and weak in refrigerant from said place of vapor expulsion tosaid place of absorption in a second path of flow in heat exchangerelation with vapor in said first path of flow, flowing liquid rich inrefrigerant from said place of absorption to said place of vaporexpulsion in a third path of flow in heat exchange relation with vaporin said first path of flow, said first path of flow constituting a placein the system in which absorption liquid normally is not circulated, andflowing liquid in said other stream through said first path'of flow andthereafter to said place of pumping for recirculation therethroughwithout passing through said place of absorption.

13. In absorption refrigeration: apparatus, a circuit for absorptionliquid comprising a generator or boiler member, an absorber, and vaporlift means for raising liquid from one level to a higher level and inwhich vapor cannot freely pass liquid therein, said vapor lift meanshaving an inlet=for liquid at the lower end thereof, and means effectiveunder all operating conditions encountered by the apparatus for dividingthe liquid in the act of raising such liquid to said higher level bysaid vapor lift means and for simultaneously flowing one part of suchdivided liquid to said absorber and from the latter to the inlet of saidvapor lift means, and for flowing another part of such divided liquid ina path of flow which by-passes said absorber and conducts liquid to theinlet :or said vapor lift means.

14. Apparatus as set forth in claim 13 in which said one part of thedivided liquid flows through said boiler member before flowing to saidabsorber.

15. Apparatus as set forth in claim 13 which includes a vertical conduitwhose lower end is connected to the inlet of said vapor lift means andin which a liquid column is maintained by liquid flowing to the inlet ofsaid vapor lift means.

16. Apparatus as set forth in claim 15 including a condenser, means forconducting vapor from said boiler member to said condenser whichcomprises said path of flow for the other divided part of the liquid andincludes a conduit communicating with said vertical conduit at a regionbelow the surface level of the liquid column maintained therein, saidvertical conduit being connected to receive liquid from said absorber ata region which also is below the surface level of the liquid columnmaintained therein.

17. In the art of refrigeration with a system having a path of flow forabsorption liquid, the improvement which comprises moving suchabsorption liquid in an upward direction in an individual stream from afirst level to a higher'level, effecting such upward movement ofabsorption liquid in the individual stream by raising successiveincrements thereof progressively higher by vapor lift action in a singlerising column under the influence of a reaction head formed by a columnof absorption liquid, dividing liquid in said individual stream byspilling liquid directly from spaced apart peripheral regions of saidsingle rising liquid column which are at the vicinity of said higherlevel and toward which absorption liquid approaches only while ascendingand moving upwardly to said higher level, and flowing in a separate pathof flow by gravity action a part of the rising absorption liquidspilling at each of said peripheral regions at the instant such liquidleaves the single column of rising absorption liquid and is no longerunder the influence of said reaction head.

18. In absorption refrigeration apparatus, a circuit for circulation ofabsorption liquid including a vapor expulsion unit and an absorber,pumping means in said circuit for raising liquid from one level to ahigher level, a vessel in said circuit which receives liquid raised tosaid higher level by said pumping means, means for conducting liquidfrom said vessel only to said'absorber and from the latter to saidpumping means at said one level, and means providing a local circuit forabsorption liquid in said vapor expulsion unit in which a portion of theabsorption liquid is constantly recirculated and never reaches saidabsorber, said local circuit including a connection into which part ofthe liquid, while moving'upwardly in saidpumping means to said higherlevel, is constantly diverted, and conduit means for conducting allliquid diverted into said connection in a path of flow which by-passessaid vessel and said absorber and communicates with said pumping meansat said one level.

'19. In absorption refrigeration apparatus, a circuit for absorptionliquid comprising a generator or boiler member, an absorber, and pumpingmeans for raising liquid from one level to a higher level, said pumpingmeans having an inlet for liquid at the lower end thereof, meansoperable at all times for dividing the liquid in the act of raising theliquid to said higher level by said pumping means, first conduit meansfor conducting one part of such divided liquid from said higher level tosaid absorber and from the latter to the inlet. of said pumping means,and second conduit means for conducting another part of such dividedliquid in a path of fiow which bypasses said absorber and conductsliquid to the inlet of said pumping means, said liquid dividing meansdiverting into said second conduit means from said pumping means a partof the liquid during upward movement thereof to said higher level.

20. In absorption refrigeration apparatus, a circuit for absorptionliquid including means providing a liquid column and a single conduithaving an inlet at the lower end thereof connected to receive liquidfrom such column which serves as a reaction head, means for effectingupward movement of liquid in said single conduit by vapor-liquid liftaction under the influence of said reaction head through a verticallyextending section of said conduit from a first level to a second higherlevel, the wall of said conduit having openings which are spaced apartfrom one another in said section thereof through which liquid onlyascends and moves upwardly to said second higher level, and meansincluding conduits communicating with said openings which provideseveral paths of flow in each of which liquid flows by gravity actionthe instant liquid passes through one of said wall openings and leavesthe liquid moving upwardly in the vertically extending section of saidsingle conduit.

References Cited in the file of this patent UNITED STATES PATENTSGaugler June 17, 1947

